drm/i915: Print PCI revision in i915_dump_device_info()

Knowing the device stepping may be crucial in analyzing problems. Since
we always ask bug reporters for dmegs with drm.debug=0xe (or something)
it would be nice if the PCI revision is already included in the dump.
Avoids having to ask for lspci output as well.
Signed-off-by: NVille Syrjälä <ville.syrjala@linux.intel.com>
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>

drivers/gpu/drm/i915/i915_dma.c

@@ -1460,10 +1460,11 @@ static void i915_dump_device_info(struct drm_i915_private *dev_priv)
 #define SEP_EMPTY
 #define PRINT_FLAG(name) info->name ? #name "," : ""
 #define SEP_COMMA ,
-	DRM_DEBUG_DRIVER("i915 device info: gen=%i, pciid=0x%04x flags="
+	DRM_DEBUG_DRIVER("i915 device info: gen=%i, pciid=0x%04x rev=0x%02x flags="
 			 DEV_INFO_FOR_EACH_FLAG(PRINT_S, SEP_EMPTY),
 			 info->gen,
 			 dev_priv->dev->pdev->device,
+			 dev_priv->dev->pdev->revision,
 			 DEV_INFO_FOR_EACH_FLAG(PRINT_FLAG, SEP_COMMA));
 #undef PRINT_S
 #undef SEP_EMPTY